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The Batticaloa Lagoon (Sri Lanka's third‐largest brackish waterbody) has suffered habitat degradation and water quality deterioration during the past 30 years due to various anthropogenic activities. Despite Sri Lanka having 40 lagoons, inventories on the lagoon ichthyofauna are rather meagre and data on fish diversity and assemblages are scarce. An assessment of fish diversity is essential to maintain the ecological stability and lagoon fisheries. This study examined the fish fauna of the Batticaloa lagoon considering the northern and southern regions of the lagoon and various depths through a 3‐year survey (2017–2019) and documented the dominant and rare fish species. In addition, biodiversity measures, species assemblages and the role of environmental parameters on the distribution of fishes were documented. Various diversity indices (the Margalef richness index, the Shannon–Weiner diversity index, Pielou's evenness index, the dominance index, the taxonomic diversity index, the average taxonomic distinctness index and the total taxonomic distinctness index) were calculated. Analysis of similarities (ANOSIM) was used to examine the seasonal and regional differences in the fish assemblages. The survey showed the occurrence of 96 species belonging to 40 families and 11 orders. Ambassis gymnocephalus was the most abundant fish species (8.7% of the total number of fishes collected) followed by Etroplus suratensis (6.8%), Arius maculatus (6.1%), Gerres filamentosus (5.3%), Oreochromis niloticus (4.6%) and Gerres abbreviates (3.9%). Dasyatis uarnak (0.02%), Acanthurus gahhm (0.03%), Alectis ciliaris (0.04%) and Crossorhombus valderostratus (0.08%) were considered as rare species which constitute less than 0.1% of the total while D. uarnak was considered a doubletons species (represented twice in the whole sample of 16 stations). Two types of species assemblages, one in the northern region and one in the southern region, were evident in a dendrogram (Based on the samples were collected on each region dendrogram were plotted with respect to sites then finally dendrogram of one region pratly connected by other region) based on sample composition similarity estimated with a Bray–Curtis matrix and nonmetric multidimensional scaling plots. The Bray–Curtis dissimilarity was 59.03% between the two regions, indicating statistically significant differences in assemblages (ANOSIM R 0.801; P < 0.01). The northern region of the lagoon had a higher number of species, density, Margalef richness, Pielou's evenness, Shannon–Wiener diversity, taxonomic diversity, taxonomic distinctness and total taxonomic distinctness compared to the southern region. The northern region showed significantly higher levels of salinity and dissolved oxygen (DO) and the southern region higher temperature, turbidity, phosphates and nitrates. The best subset of biota and environmental variables [BEST(BIO‐ENV)] test showed a significant relationship between fish assemblage and environmental parameters. Distance‐based linear model analysis showed a significant relationship between fish assemblage and the environmental parameters salinity, temperature, pH and DO. The sequential test of this analysis showed the environmental parameters to explain about 74.9% (R2) of the total variation. The bioenvironmental model developed was found to be appropriate. Thirteen species were found to be influential as they explained the overall fish distribution pattern with a Spearman rank correlation of 0.951. Ten groups of coherent species were also identified in the study area. In stations having anthropogenic activities, the fish diversity was low. The fish fauna of the Batticaloa lagoon should be monitored periodically to protect the fishery resources here. An understanding of the role that environment plays in structuring the fish assemblage in the Batticaloa lagoon and locations with critical habitats will be of great importance in the conservation and management of fishery resources in this lagoon. However, as monitoring only the dominant species may fail to pick up on important impacts affecting the less common species, it should be done using diversity indices and rare fish species. Monitoring is imperative in view of the livelihood of the fishers this lagoon supports and the health of the local people, as fish is a healthy food. The fishery resources of this lagoon must be protected for posterity with appropriate management measures. [ABSTRACT FROM AUTHOR]

This article discusses bioaccumulation and temporal variation of heavy metals in three edible lagoon fish species with references to gender. Cd and As were undetected in the three fish species (i.e., below the method detection limits of 1 μg Cd/kg wet weight and 2 μg As/kg wet weight) irrespective of the periods, and Cd was undetected in the water too (i.e., below the detection limit of 0.0003 mg/L). Except for Zn (which was mainly available as Zn in the water), Pb was present largely as low labile metal-chloride complexes and As as HAsO as per Visual MINTEQ, version 3.1. Bio-transfer factors of Sn (which was also undetected in the water; below the detection limit of 0.05 mg/L), Hg, Pb, and Zn were <1 in both sexes, justifying that bioaccumulation was largely attributed to food rather than uptake from the water. Metal accumulation patterns differed drastically between the fish species. Arius maculatus (a carnivore) exhibited higher Zn, Hg, and Sn accumulations during the drier periods (June-September) compared with Mugil cephalus (a detritivore/herbivore) and Etroplus suratensis (an omnivore). Pb was detected only in A. maculatus (July-August) possibly due to biomagnification. Zn was present in higher levels in all species (irrespective of sex) compared with the other metals, but levels were below admissible limits. However, the relationship between temporal variation of Zn and gender in all species was insignificant. In M. cephalus, the temporal variation of Sn and Hg between the sexes was also insignificant. Female A. maculatus and E. suratensis showed higher Hg concentrations, while males showed higher Sn concentrations. Temporal variation patterns of Pb were unclear. [ABSTRACT FROM AUTHOR]

The necessity to understand the relationship between cyanobacterial species abundance and water quality variations in coastal lagoons is crucial to develop strategies to prevent further cyanobacterial proliferation. This paper evaluates the relationship between water quality variations on the distribution of cyanobacteria during a 12-month period in Batticaloa Lagoon (Sri Lanka) using Redundancy analysis and Pearson correlations. Drastic variations in pH, temperature, salinity, dissolved oxygen (DO) and total phosphorus (TP) levels were reported, but not turbidity and NO 3 − . This brackish waterbody is hypereutrophic (TP levels > 0.1 mg/L). The cyanobacterial community contained 13 genera and 22 species. NO 3 − , TP and turbidity levels positively influenced cyanobacterial abundance during all seasons indicating that nutrient (largely phosphorus) and sediment entry control is highly crucial along with periodic monitoring of cyanobacterial growth. [ABSTRACT FROM AUTHOR]

Purpose |!|#8211; The purpose of this study is to investigate the concept of knowledge management (KM) readiness using intention to be involved in the KM processes concept. These processes comprised of socialisation, externalisation, combination, and internalisation (SECI processes). The research also attempts to measure and validate the concept using data collected from the Sri Lankan telecommunication industry. Design/methodology/approach |!|#8211; Based on the established KM SECI process measures adopted and adapted, instruments were administered using a survey research methodology approach on 313 executives working in the selected organizations in the Sri Lankan telecommunication industry. A confirmatory factor analysis technique was performed to verify and validate the measurement model of the intention to be involved in KM processes model. Based on the revised measurement model, the level of intention to be involved in the KM SECI processes within the industry was then reported. Findings |!|#8211; The research finding provides the revised measurement model for employees|!|#39; intention to be involved in KM SECI processes. All four variables of the intention to be involved in KM SECI processes emerged as significant and reliable measures for KM readiness. The finding also indicates the positive level of intention among the employees in the Sri Lankan telecommunication industry to be involved in KM processes. Originality/value |!|#8211; The research provides a unique perspective of KM readiness, which is not much covered in the KM literature. The measurement produced can be used as a research tool for more exploratory and explanatory research in KM and, as an evaluative tool for employee readiness in ensuring the success of KM initiatives in organizations. The confirmed and validated set of measurement items can be used to measure the extent to which employees are ready to be involved with KM processes. Through the validated tool, more research can be conducted to explore the antecedents of such readiness perception. [ABSTRACT FROM AUTHOR]